Exchangeable Oil Filter With Spring-Operated Pin For Drainage

ABSTRACT

The invention relates to a device for filtering of oil circulating in an internal combustion engine, comprising an oil filter adapter  2  for detachable fastening of an exchangeable oil filter  3  to the engine block  1  of the internal combustion engine. The invention is characterized in that the oil filter adapter  2  has a receptacle  13  with an inserted pin  14 , the receptacle  13  having an outflow  10  for returning the oil flowing from the exchangeable oil filter  3 , the receptacle  13  having a channel  11  which leads in particular to an oil pump, and the receptacle  13  having a drain  12  which leads in particular to the cylinder crankcase, the pin  14  being inserted elastically pretensioned such that during operation the pin  14  clears the outflow  10  and closes the channel  11  and the drain  12 , and, when the exchangeable oil filter  3  is loosened from the oil filter adapter  2 , the pin  14  is displaced by spring force and clears the outflow  10 , the channel  11 , and the drain  12 . Furthermore the invention includes a pin which is designed for use in the device according to the invention.

The invention relates to a device according to the preamble of claim 1.

Internal combustion engines of motor vehicles have exchangeable oilfilters for cleaning the oil; they are connected to the internalcombustion engine so that the oil from the internal combustion enginecan circulate through the exchangeable oil filter and back again to theinternal combustion engine. Exchangeable oil filters such as these, forexample, have a filter insert which can be completely incinerated andare generally changed or replaced at fixed intervals together with theoil of the internal combustion engine. For this purpose the exchangeableoil filter has a thread for simple replacement, with which it can beinserted and screwed tightly into a corresponding opening of the oilfilter adapter on the engine block of the internal combustion engine. Inaddition, seals for improving the seal before installing theexchangeable oil filter are used. Furthermore, exchangeable oil filtersare known from the prior art which have a drainage pin.

But the disadvantage is that residual oil remains in the engine when theexchangeable oil filter is replaced.

Therefore the object of the invention is to make available a device inwhich residual oil does not remain in the engine when the exchangeableoil filter is replaced.

This object is achieved according to the invention in the characterizingfeatures of the main claim. Advantageous embodiments of the inventionare described by the dependent claims.

The invention is based on the elastically pretensioned pin acting as avalve which during operation, that is, when oil is circulating, holds anoutflow open through which cleaned oil coming from the exchangeable oilfilter is returned again to the engine; while a channel which leads inparticular to the oil pump and a drain which leads to the crankcase areclosed. If, however, the exchangeable oil filter is separated or removedfrom the oil filter adapter, the pin which acts as a valve automaticallyopens the channel which leads to the oil pump and the drain which leadsto the cylinder crankcase so that a first connection from the outflow tothe drain and a second connection from the channel to the drain arecleared, so that the residual oil in die region of the outflow and inthe region of the channel as well as within the pin can automaticallyrun out, i.e., under the action of gravity.

One embodiment of the invention is explained below using the drawings.

FIG. 1 shows in a sectional view an engine block with an oil filterholder into which a pin is inserted and to which an exchangeable oilfilter is attached in its mounting position,

FIG. 2 shows in a sectional view an engine block with an oil filterholder into which a pin is inserted, in which in contrast to FIG. 1 anexchangeable oil filter has been loosened for replacement,

FIG. 3 shows a perspective view of a pin.

Reference is made first to FIGS. 1 and 3.

The engine block 1 of an internal combustion engine has an oil filteradapter 2 which can be mounted detachably or non-detachably on theengine block 1. Above the engine block 1 an exchangeable oil filter(shown in a section) is detachably mounted, for example, by means of athread and, for example, has a filter insert (not shown) which can becompletely incinerated. The exchangeable oil filter 3 has an inlet 4 andan outlet 5 which are both pointed down, the outlet 5 being located on aconnecting piece which projects in the screw-in direction 6.

The engine block 1 furthermore has a first space 7 with an inflow 8which establishes a connection to an oil pump (not shown) for thecirculating oil. A second space 9 of the engine block 1 is located abovethe first space 7 and establishes a connection to the inlet 4 of theexchangeable oil filter 3 for the circulating oil.

The oil filter adapter 2 has a receptacle 13 which has an annularly madecollar 15 on which a pin 14 which is inserted in the receptacle 13rests. The receptacle 13 of the oil filter adapter 2 has an outflow 10through which oil coming from the exchangeable oil filter 3 can bereturned to the engine. Underneath the outflow 10 there is a channel 11which can establish a connection from the receptacle 13 to the firstspace 7 of the engine block 1. Furthermore the receptacle 13 of the oilfilter adapter 2 has a drain 12 which is located underneath the channel11 and which can establish a connection to the cylinder crankcase (notshown).

The pin 14 in the receptacle 13 consists essentially of a base body ofcylindrical shape and has a passage 16 which establishes a connection tothe outlet 5 of the exchangeable oil filter 3 for the circulating oil.The passage 16 of the pin 14 is connected to a plurality of slot-likeradial openings 17 so that oil from the outlet 5 of the exchangeable oilfilter 3 can flow through the passage 16 and the radial openings 17 ofthe pin 14 to the outlet 10.

On its lower end (see FIG. 3) the pin 14 has a first seal 18 and asecond seal 19, the first seal 18 of the pin 14 and the receptacle 13being made such that in the mounting position shown in FIG. 1 thechannel 11 is closed. Furthermore the second seal 19 and the receptacle13 are made such that the drain 12 is closed in the mounting-positionshown in FIG. 1.

The pin 14 (see FIG. 3) on its upper end has a contact surface 20 andunderneath it an annularly made bearing surface 21. Between the contactsurface 20 and the bearing surface 21 of the pin 14 there is a helicalspring which is dynamically connected to the contact surface 20 and thebearing surface 21 such that the helical, spring 22 can be compressed byreducing the distance between the contact surface 20 and the bearingsurface 21. The helical spring 22 can, for example, have a diameter of23×2 mm. Instead of the helical spring 22, however, other suitablespring elements can also be used. Furthermore the pin 44 has three stopmeans 23 which are spaced uniformly on the periphery of the bearingsurface 21, which are made in the shape of projections and in thepositions shown in FIG. 3 adjoin the bearing surface 21 and preventfurther release of the helical spring 22.

In the mounting position (see. FIG. 1) the contact surface 20 is incontact with the connecting piece 6 of the exchangeable oil filter 3while the annular bearing surface 21 engages the corresponding collar15. In this mounting position the helical spring 22 is compressed sothat the helical spring 22 is elastically pretensioned, for example,with 15 mm.

During operation, with the channel 11 closed and the drain 12 closed,the oil which is under a pressure p₁ flows out of the inflow 8, forexample, coming from an oil pump, into the first space 7 from which theoil is routed, for example, through an oil cooler (not shown). Comingfrom the oil cooler the oil which is under a pressure p₂ flows into thesecond space 9, from which it is routed through the inlet 4 into theexchangeable oil filter 3. The oil leaving the exchangeable oil filter 3through the outlet 5 is under a pressure p₃, p₃<p₂<p₁ applying to theratio of the magnitudes of the pressures p₁ to p₃. From the outlet 5 ofthe exchangeable oil filter 3 the circulating oil flows down through thepin 14 with its passage 16 and the radial openings 17 into the channel11 and is then routed to the engine.

At this point reference is additionally made to FIG. 2.

When the exchangeable oil filter 3 is loosened, for which, for example,several turns are necessary, the position of the exchangeable oil filter3 shown in FIG. 2 is reached. In this position the helical spring 22 ofthe pin 14 is relieved so that in the unscrewing direction of theexchangeable oil filter 3 the pin 14 is automatically displaced axially.

As a result of this motion, the first seal 18 of the pin 1 no longercloses the channel 11 so that residual oil 11 which is located in thechannel 11 and/or in the first space 7 can automatically travel to thedrain 12 which is likewise opened by this motion. The second seal 19 asa result of this motion furthermore no longer closes the outflow 10 sothat the residual oil which is located in the outflow 10 can likewisetravel automatically past the opened first seal 18 to the drain 12.Furthermore, the residual oil which is located in the receptacle 13 orwithin the pin 14, for example, in the passage 16, can run outautomatically through the drain 12 through which the residual oil cantravel into the cylinder crankcase (not shown). When the residual oilhas run out, the exchangeable oil filter 3 can be removed.

Finally, a new exchangeable oil filter 3 is mounted and screwed tight sothat again the position shown in FIG. 1 is reached. The pin 1 isdesigned such that when the new exchangeable oil filter 3 is mounted,first roughly 2 turns of the thread engage and then, as turningcontinues, the face surface of the connecting piece 6 comes into contactwith the pin 1 and then the pin 1 is displaced against the spring 22.

REFERENCE NUMBER LIST

-   1 engine block-   2 oil filter adapter-   3 exchangeable oil filter-   4 inlet-   5 outlet-   6 connecting piece-   7 first space-   8 inflow-   9 second space-   10 outflow-   11 channel-   12 drain-   13 receptacle-   14 pin-   15 collar-   16 passage-   17 radial opening-   18 first seal-   19 second seal-   20 contact surface-   21 bearing surface-   22 helical spring-   23 stop means

1. A device for filtering of oil circulating in an internal combustionengine, comprising an oil filter adapter (2) for detachable fastening ofan exchangeable oil filter (3) to the engine block (1) of the internalcombustion engine, characterized in that the oil filter adapter (2) hasa receptacle (13) with an inserted pin (14), the receptacle (13) havingan outflow (10) for returning the oil flowing from the exchangeable oilfilter (3), the receptacle (13) having a channel (11) which leads inparticular to an oil pump, and the receptacle (13) having a drain (12)which leads in particular to the cylinder crankcase, the pin (14) beinginserted elastically pretensioned such that during operation the pin(14) clears the outflow (10) and closes the channel (11) and the drain(12), and, when the exchangeable oil filter (3) is loosened from the oilfilter adapter (2), the pin (14) is displaced by spring force and clearsthe outflow (10), the channel (11) and the drain (12).
 2. The deviceaccording to claim 1, characterized in that in the inserted state thepin (14) can be axially displaced in the direction of the looseningmotion when the exchangeable oil filter (11) is loosened.
 3. The deviceaccording to claim 1 or 2, characterized in that the spring force ismade available by a helical spring (22).
 4. The device according to oneof claims 1 to 3, characterized in that the pin (14) has a bearingsurface (21) which is made for interaction with a connecting piece (6)of the exchangeable oil filter (3).
 5. The device according to one ofclaims 1 to 4, characterized in that the pin (14) has a first seal (18)which during operation is located between the channel (11) and the drain(12) and that the pin (14) has a second seal (19) which is locatedbetween the outflow (10) and the channel (11) during operation.
 6. Thedevice according to one of claims 1 to 5, characterized in that theoutflow (10) is located above the channel (11) and that the channel islocated above the drain (12).
 7. The device according to one of claims 1to 6, characterized in that with the outflow (10), channel (11), anddrain (12) cleared the oil can essentially drain automatically.
 8. A pinwhich is designed to be used in a device according to one of claims 1 to7.